Getting back to one of doodlehead's questions about if there is a difference in shaving between a metal razor and non-metal, here is something similar where one may scrape an animal [eg. to remove insects] with a wooden scraper even if it's possible hair will be removed and wound result but not with a metal scraper since the latter will inevitably cause hair to come out [a pesik reisheih]

But this seems to be a heter of davar shein miskavein, so probably the issue is probably the sharpness of the scraper as opposed to it's material, so that a sharp wooden scraper would probably be asur. It is 
possible that the chidush here is that even a blunt metal scraper would cause 
enough friction to create a psik reisha. (I haven't seen the tur inside... I'll get around to it soon bli neder...)  

Yes, I agree. Also, keep in mind when shaving, the purpose is to shave, whereas when removing insects with a wood or metal scraper, the purpose is to remove insects while the removal of hair is incidental. So in fact there is no derivation of one case [shaving] from the other [this one].

Thanks
Yep, we're adding it to the list of unaswered doodlehead questions.

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